Abiotic stress treatment reveals expansin like A gene OfEXLA1 improving salt and drought tolerance of Osmanthus fragrans by responding to abscisic acid  

作　　者：Bin Dong Qianqian Wang Dan Zhou Yiguang Wang Yunfeng Miao Shiwei Zhong Qiu Fang Liyuan Yang Zhen Xiao Hongbo Zhao 

机构地区：[1]School of Landscape Architecture,Zhejiang Agriculture and Forestry University,Hangzhou,Zhejiang 311300,China [2]Zhejiang Provincial Key Laboratory of Germplasm Innovation and Utilization for Garden Plants,Hangzhou,Zhejiang 311300,China [3]Key Laboratory of National Forestry and Grassland Administration on Germplasm Innovation and Utilization for Southern Garden Plants,Hangzhou,Zhejiang 311300,China

出　　处：《Horticultural Plant Journal》2024年第2期573-585,共13页园艺学报（英文版）

基　　金：supported by the National Natural Science Foundation of China (Grant Nos.31902057 and 32072615);Zhejiang Provincial Natural Science Foundation of China (Grant No.LQ19C160012);the key research and development program of Zhejiang Province (Grant No.2021C02071)。

摘　　要：Sweet osmanthus(Osmanthus fragrans) is a having general approval aromatic tree in China that is widely applied to landscaping and gardening. However, the evergreen tree adaptability is limited by many environmental stresses. Currently, limited information is available regarding the genetic analysis and functional identification of expansin genes in response to abiotic stress in sweet osmanthus. In this study, a total of 29 expansin genes were identified and divided into four groups by genome-wide analysis from the sweet osmanthus genome. Transcriptome and quantitative Real-time PCR analysis showed that the cell wall-localized protein expansin-like A(OfEXLA1) gene was significantly induced by salt and drought treatment. Histochemical GUS staining of transgenic Arabidopsis lines in which GUS activity was driven with the OfEXLA1 promoter, GUS activity was significantly induced by salt, drought, and exogenous abscisic acid(ABA). In yeast, we found OfEXLA1overexpression significantly improved the population of cells compared with wild-type strains after NaCl and polyethylene glycol(PEG)treatment. Additionally, OfEXLA1 overexpression not only promoted plant growth, but also improved the salt and drought tolerance in Arabidopsis. To gain insight into the role of ABA signaling in the regulation of OfEXLA1 improving abiotic tolerance in sweet osmanthus, four differentially expressed ABA Insensitive 5(ABI5)-like genes(OfABL4, OfABL5, OfABL7, and OfABL8) were identified from transcriptome, and dualluciferase(dual-LUC) and yeast one hybrid(Y1H) assay showed that OfABL4 and OfABL5 might bind to OfEXLA1 promoter to accumulate the OfEXLA1 expression by responding to ABA signaling to improve abiotic tolerance in sweet osmanthus. These results provide the information for understanding the molecular functions of expansin-like A gene and molecular breeding of sweet osmanthus in future.

关 键 词：Osmanthus fragrans Abiotic tolerance EXPANSIN Abscisic acid 

分 类 号：S685.13[农业科学—观赏园艺]